Background to the Survey

1
Background to the Survey

• Rachael Harker, ONS

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Childrens Dental Health Survey

• Decennial survey run since...
• 1973 - England and Wales, 1983 - United
  Kingdom
• Commissioned by UK health departments
• Carried out by consortium
• ONS, University Dental Schools of Birmingham,
  Cardiff, Dundee, Newcastle and DHSRU, Dundee
• Survey components
• Clinical examination - school based sample of
  5, 8, 12 and 15 year olds
• Parental questionnaire - postal questionnaire
  sent to random sub-sample of 50 of parents of
  examined children

3
Examination criteria

• Tooth condition
• - revised to include visual as well as
  cavitated dentine caries
• Tooth surface loss
• - extended to include first permanent molars
• Enamel defects
• Accidental damage to incisors
• Periodontal Health
• - periodontal assessment for 15 year olds
  restricted to presence of
• gingivitis
• Orthodontic condition
• - simplified Index of Orthodontic Treatment Need
  (IOTN)

4
Parental questionnaire

• Dental attendance patterns
• Dental services used
• Treatments experienced
• Dental care at home
• Views on causes/prevention of tooth decay
• Attitudes towards appearance of childrens
  teeth

5
Parental questionnaire

• New for 2003
• Barriers to dental care
• Marks on teeth
• Impact of oral health
• Referral to an orthodontist

6
Sample Requirements

• Separate analysis of each sampled year cohort
  according to
• gender
• country (England, Wales, Northern Ireland)
• region (England, Wales)
• school deprivation status
• Geographical clustering
• To minimise examiner travelling time and workload
• (England, Wales, Scotland)

7
Sampling frames

• Schools
• All maintained and independent primary and
  secondary schools
• Children
• Lists of all children aged 5, 8, 12 and 15 on
  31 August 2003
• provided by participating schools
• Exclusions
• Special Schools
• Schools in Isle of Skye, Shetland, Orkney and
  Eilean Sar

8
Sampling procedure

• England, Scotland and Wales
• Sampling regions
• 72 Local Authority Districts - England
• 24 Unitary Authorities - Wales
• 8 Education Authorities - Scotland
• Sampling schools
• Primary schools grouped with secondary
  schools
• One school group per region selected with
  probability
• proportional to size (with replacement)
• Northern Ireland
• Simple random sample (with replacement)

9
Sampling procedure

• Sampling children
• England, Scotland and Wales
• 37 children from each age cohort sampled in
  each school group
• Northern Ireland
• 9 children age 5 and 8 years in each primary
  school
• 27 children aged 12 and 15 years in each
  secondary school

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Sampling procedure

• Sampling parents
• Parents of 50 of examined children ( those who
  were allocated a odd number in their unique
  survey serial number).

11
Examiner training

• 66 dental teams (examiner and recorder)
• Pre-training interactive CD-Rom
• 3 day training period
• - Clarification of criteria
• - Practice examinations
• - Calibration exercise

12
Calibration

• Focus on caries
• 8 groups of dental examiners
• 10 groups of children
• Cohens Kappa
• Substantial agreement between examiners
• Kappas ranged from 0.62 to 0.91

13
Fieldwork arrangements

• School based examinations
• Advance information letters sent to parents via
  schools
• Opt out procedure
• - Withdrawal in advance via school or ONS
  freephone
• - Refusal from child on day of
  examination

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Fieldwork arrangements

• Schools provided
• - Private room or space with natural
  light
• - Table
• Examiners provided daray lamps
• Approximate examination length
• - 5 minutes (primary)
• - 8 to 10 minutes (secondary)

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Response

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Response
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Response
18
Data Processing and Weighting

• Data coding and cleaning
• Creation of derived variables
• Weighting the data
• - weighting back to population proportions
• - non-response
• Combined weight produced for examination and
  questionnaire data

19
Acknowledgements

• LEAs, headteachers and school staff
• Survey dentists and dental nurses
• Participating children and parents
• Central Survey Unit, NISRA
• Jan Gregory (1946 - 2004)

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Further information

• CDH Technical Report
• http//www.statistics.gov.uk/children/dentalhealth